Method of and apparatus for sealing pasteboard cans



L. L. LADD Nov. 11, 1941;

METHOD OF AND APPARATUS FOR SEALING PASTEBOARD CANS Filed Sept. 18, 1939 5 Sheets-Sheet 1 5391 llllllll L. L. LADD Nov. 11, 1941.

METHOD OF AND APPARATUS FOR SEALING PASTEBOARD CANS Filed Sept. 18, 1939 g 1 9 afozzzegw METHOD OF AND APPARATUS FOR SEALING PASTEBOARD CANS Filed Sept. 18, 1959 5 Sheets-Sheet 3 Nov. 11, 1941. L. L. LADD 2,262,292

METHOD OF AND APPARATUS FOR SEALING PASTEBOARD CANS Filed Sept. 18, 1939 5 Sheets-Sheet 4 Nov. 11, 1941. L. L. LADD 2,262,292

METHOD OF AND APPARATUS FOR SEALING PASTEBOARD CANS Patented. .Nov. 11, 1941 UNITED STATE s PATENT OFFICE METHOD OF AND APPARATUS FOR SEALING PASTEBOARD CANS Lester L. Ladd, Lockport, Ill. Application September 18, 1939, Serial No. 295,351

'. 15'Claims. (61. 93-551) label, bearing the name, of the goods and the name and-address of the manufacturer, is rolled around and adhered to the can, this label being wide enough to cover not only the body of the can but also the major portion'of the flanges of the caps.

Now, since the cap flanges encircle the end por- V tions of the can body; the external diameter of' the cap flanges is greater by twice the thickness of the cardboard stock than the external diameter of the ends of the body. As a consequence of this, when the labelis appliedto side portions thereof which encircle the cap flanges are required to cover an area of greater circularextent than the main portion thereof which covers the can body, and this creates an oblique stretching strain on the parts of the label which overlie the joints at the inner edges of the cap flanges, which often results in breaking the label, moistened and weakened by the wet paste, lessening the emciency of the label as a cap looking or bonding means. Furthermore, it destroys the straight line effect of the exposed edge of the label ex tending from end to end of the can. i

The main object of this invention has been to provide an improved method and apparatus for sealing fllled pasteboard cans or cartons having flanged end closures or caps that will effectively obviate the above noted objections.

Still other objects andattendant advantages of theinvention will be apparent to persons skilled in the art from the following detailed description, taken in connection with the accompanying drawings in which I.have illustrated one practical and preferred embodiment of both the can itself and the method of and apparatus for'making the same, and in which- Fig. l is a perspective view of the can in its initial stage, with the caps to the can body. I

Fig. 2 is an elevation of the can with the caps moistened and applied.

Fig. 3 is an elevation of the can with the caps applied and compressed on the ends of the body, and showing in section the cap clamps.

Fig. 4 is a fragmentary view enlarged of the upper portion of a filled can, showing in section label applied.

the inwardly offset joint between the can and cap.

. Fig. 5 is an elevation of a sealed can with the Fig. 6 is a view similar to Fig. 4 of an end portion of a filled, sealed and labeled can.

Fig. '7 is a top plan view of the cap compressing and locking mechanism, including the can feeding and discharging devices.

Fig. 8 is a side elevation of the mechanism shown in Fig. 7, viewed from the bottom of Figl'7, with the heater omitted for the sake of clearness.

Fig. 9 is a vertical transverse section on the line 5-9 of Fig. '1.

Fig. 10 is an enlarged plan section, taken on the line l0-l0 of Fig. 9.

Fig. 11 is a detail vertical section, taken on the line Hll of Fig. 7. a

Fig. 12 is a perspective view of part of an automatic trip mechanism that controls the feeding of the cans into the compressing and squeezing mechanism.

about to be applied Describing first the apparatus, the working parts are supported on a rectangular frame comprising parallel longitudinal angle bars l5 supported at their ends on legs is, to the lower ends of which are attached feet H. The two legs at each end are connected and spaced by a tie rod l8, and the tops of the angle bars I5 are rigidly connected and spaced by transverse plates [9, 2B and 2|. 0n the plates l9 and 2| are mounted bearings 22 (Figs. 8 and 9) for vertical shafts 23, and the upper ends of said shafts are also journaled in bearings 24 formed on the ends of lateral arms 25 on the upper ends of posts 26 rising from the base plate of the lower bearings 22. Flat. transverse bars 21 rigidly connect and space the arms 25 at each end of the machine. Keyed on the shafts 23 between the shaft bearlugs 22 and 24 are hubs 28, integral-with the upper and lower end portions of which are sprocket wheels 29 and 30. Trained around these sprocket wheels are two endless belts extending in substantial parallelism lengthwise of the machine,-

each belt consisting of upper and lower chains chains 3| and 32.

with the platform 49 is a board 52.

each belt. Each clamp includes a fiat rectangular base plate 38 that is attached at one side of its vertical median line, as by rivets 39 (Fig. 9) to vertical extensions 40 of spaced links of the As best shown in Figs. 7 and 9, the third link in rear (in the direction of travel) of the link to which the plate 36 is attached is formed with similar vertical extensions 4| which contact with the plate 38 on the other side of the vertical median line of the latter except when the clamps are rounding thesprocket wheels, thus affording two horizontally spaced er) of substantially semicircular horizontal'grips 42 rigidly connected and spaced by an integral One arm 14 of this elbow lever has an upturned free end 15 that normally abuts against the latch 69 in position to release the latch from the finger 66. The other arm 16 of the elbow lever carries on its free end a roller 11 that cooperates with notches or cams 18 in the periphery of a disc 19 that is fast on the lower end of one of the sprockthe stop finger 66 and thus permit the next can to vertical bar 43 (Fig. 8) and having concave can-f,

by rivets 39' (Fig. 8).

Attached to and supported on vertical brackets 48 (Fig. 9) stepped on the cross plates l9 and 2! is a platform 49 located parallel'with and midway between the adjacent laps of the belts: and adjustably suspended by threaded rods 50 and nuts 5| from the bars 21 above and parallel The platform'49 and board 52 are spaced the height of the cans that travel between them.

Flanking the adjacent laps of the chains 3| and 32 are upper and lower bars 53 and54 (Figs. 10 and 11), the inner edges of which are formed as low cams 55 having their peaks at the points 56. These bars 53 and 54 are supported at their ends on horizontal lugs 51 projecting from the legs 26, and the bars are adjustable toward and from the chains whichslidably engage their cam edges by screws 58 threaded through the legs 26 and engaged with the outer edges of the bars; and the latter are secured in adjusted position by clamp screws 59 extending through transverse slots 60 in the bars and entering tapped holes v in the lugs 51.

Referring to Fig. 7, at BI is shown the inner end of a belt conveyor that carries the cans into the machine, and at 62 is shown a discharge conveyor. A stop 63 constituting a continuation of the inner wall of a curved passageway 64 leading from theconveyor 6! to the entrance end of the platform 49 arrests theforemost can-in position to be deflected into and through the pas sageway 64. Thecan deflectingpmeans consists of a thin arm 65 on the trailing end of the clamp that projects far enough laterally to engage the foremost canon the, conveyor 6| and push it into the passageway 64, through the latter, and through the zone, of the can clamping and' spring 68, and held in stop position by a latch 69 pivoted at 10 and retained in latching position 'with the outer end of the finger 66 by a spring ll.

Stop finger 66 is unlatched as soon as the foremost can has passed off the conveyor 6| and into the passageway 64' by an elbow lever, best shown in the perspective view,'Fig.' 12, that is pivoted at I2 on a post 13 supported on the frame (Fig. 8).

advance to discharge position. When this has happened, the roller I1 is forced outwardly into engagement with the periphery of the cam disc 19, and this reseats the parts of the trip to the position shown'in Fig. 7.

When the apparatus is operating upon pasteboard or other fibrous cans, preferably the entirecap is stamped from pasteboard or paper that has previously been dampened; or the flange of a preformed can cap or cover may be dampened or moistened before it is applied; and the eiiiciency of the clamps or squeezers to effect the inward offsetting of the flange and the portion of the can body encircled thereby is enhanced by heating the clamps or squeezers just before they engage'with the cap flanges. For this purpose I provide opposite the outer laps of the chain belts, gas heaters 80 supplied, by a manifold 8|, and equipped with burners 82 (Fig. 9) by which fiames are directed onto the flange grips 42, heating the latter sufliciently to cause them to convert the residual moisture in the damp flanges of the caps into steam, which penetrates and softens the portion of the can body encircled thereby, thus enabling such portions to be offset inwardly without cracking or breaking.

The drive mechanism for the chain belts is best shown in Figs. 8 and 9. Attached to the outer sides of he frame angle bars l5, as by maand treatment of the pasteboard cans.

chine screws 83, are brackets 84, the lower portions of which are formed to constitute bearings '85 for a transverse drive shaft 86, on one end of which is keyed a sprocket wheel 81 driven by a sprocket chain 88 from any suitable source of power. Keyed on. the shaft 86 is a miter gear 89 meshing with and driving a miter geazl9ll secured by machine screws 9| to the lower side of a large horizontal gear wheel 92 that is keyed on one of the'shafts 23. Gear wheel 92 meshes with and drives a similar gear wheel 93, the hub of which encircles the companion shaft 23, and to the lower side of gear 93 is attached by machinelscrews 94 a disc 95 that is keyed to the lower en'd'of the companion shaft 23.

In describing the operation of the apparatus I shall refer to Figs. 1 to 6, inclusive, which illustrate various stages in the formation, loading A desighates the cylindrical body of 'a pasteboard can,

and B designateseach of the upper and lower covers or caps, each of which is formed with an annular flange or rim b that is first dipped in water or otherwise" moistened, the can caps being then applied to the bodyas shown in Fig. 2.

Prior to applying the upper cap, the can is forced inwardly in a direction at right angles to the axes of the caps, as shown in Fig. 3. The grips 42 are somewhat wider than the flanges b, as shown in Fig. 3, and they engage with the flanges slightly below the joints of the flanges body encircled thereby are" inwardly offset, as? shown in Figs. 4 and 6, and furthermore, a-shal low internal annular groove D is formed. at the,

junction of the flange with the disc,and'an outwardly offset annular bead. E. is formedaon, the upper edge of the can body, which yieldably'in-a terlocks with the groove D in the-manner-qclearly shown in Figs. 4.and 6. When the chain belts have passed off the peaks ii of the cams, the gripsbegin to retreat fromv the can and this continues until the can is fully released, and delivered onto the discharge conveyor 62. The groove D and bead E do not permanently lock the cap on thebody, but they do yieldably lock it against accidental displacement in handling. This yield-v able lock. forms the subject matter of a divisional application filed by me December 16, 1940, Serial No. 370,361.

As will be seen by Figs. 4, 5 and 6, this treatment brings the outer surfaces of the flanges b flush with the outer'surface of the can body between the flanges, so that. when a paper label, such as F is rolled on the can with its side edge portions overlapping the flanges b, there is no warping or stretching between the parts of the label that cover the flanges and the part that covers the intermediate body portion of the can, thus leaving the surface of the label perfectly smooth and straight from end to'end of the can.

I have herein shown and described one practical and preferred embodiment of this invention, but it is manifest that, so far as themethod and apparatus are concerned, changes in the details of structure and arrangement may be resorted to without departing from the operative principle or sacrificing any of the advantages of the invention. Hence, I reserve all such variations, modifications and mechanical equivalents as fall within the spirit and purview of the appended claims.

I claim:

1. In an apparatus of the class described, the combination with means for supporting a cylindrical pasteboard can having apasteboard cap with a flange encircling an,,end'portion of the can body, of a pair of clamps formed with opposed substantially semi-circular flange fitting surfaces, and means for effecting simultaneous inward movements of said clamps at rightangles to the axis of the cap into squeezing engagement with said flange sufficient to inwardly offset the portion of the body encircled by the flange and bring the outer surface of the flange flush with the outer surface of the can body.

2. In an apparatus of the class described, the combination with means for supporting a cylindrical pasteboard can having a pasteboard cap with a moistened flange encircling an end portion of the can body, of a pair of clamps formed with opposed substantially semi-circular flange fitting surfaces, means for heating said clamps, and means for effecting simultaneous inward movements of the heated clamps at right angles to the axis of the cap into squeezing engagement travel both the flanges and the portions of,the

with said flange suflicient to inwardly offset the,

portion of the body encircled by the flange and bring the outer surface of the flange flush with the outer surface of the can body.

3. In an. apparatus of the class described, the combination of a platform, meansforv-successively feeding onto one end of said platform cylindrical pasteboard cans having caps. with, flanges encircling the ends of." they can bodies; endless .belts mounted on opposite, sidesrespectively of,

and substantially parallel with, said. platform,

clamps formed with substantially semisci rcular flange fitting surfaces carried, by saidbelts, and means for gradually moving said clamps. at right angles to the axes of the caps, into. squeezing engagement. with the cap flanges.during:the passage of the-cans over said platform: between adjacent laps of saidbelts.

4. In an apparatus of the-class described, the combination of 'a platform; means for successive- 1y feeding onto one end of said platform cylindrical pasteboard cans having caps: with flanges encircling the ends of. the, canfibodies, endless belts mounted on. opposite, sides. respectively of, and substantially parallel with, said platform, clamps formed with substantially semi-circular flange fitting surfaces carried by said belts, means for heating said clamps prior to their engagement with the cans, and means for gradually moving said clamps at right angles to the axes of the caps into squeezing engagement with the cap flanges during the passage of the cans over said platform between adjacent laps of said belt.

5. In an apparatus of the class described, thecombination of a platform, means for successively feeding onto one end of said platform cylindrical pasteboard cans having caps with flanges encircling the ends of the can bodies, endless belts mounted on opposite sides respectively of,

and substantially parallel with, said platform, clamps formed with substantially semi-circular flange fitting surfaces carried by said belts, and stationary cams located respectively on opposite sides of said platform and engaged by said clamps for gradually moving the latter into squeezing engagement with the cap flanges during the passage of the cans over said platform between adjacent laps of said belts.

6. In an apparatus of the class described, the combination of a platform, means for successively feeding onto one end of said platform cylindrical pasteboard cans having caps with flanges encircling the ends of the can bodies, endless belts mounted on oppositelsides respectively of, and substantially parallel iyith, said platform, clamps formed with substantially semi-circular flange fitting surfaces carried by said belts, gas burners located opposite theouter laps of said belts adapted to direct flames on said clamps to heat the same, and stationary cams located respectively on opposite sides of said platform and engaged by said clamps for gradually moving the latter into squeezing engagement with the cap flanges during the passage of the cans'over said platform between adjacent laps of said belts.

7. In combination with the subject-matter deflned in claim 3, a plank overlying the platform parallel therewith and spaced therefrom the height of the cans.

'8. A specific embodiment of the combination defined in claim 3, wherein the means for successively feeding the cans onto one end of the platform comprises a belt conveyor, a'lateral passageway leading from the delivery end of said conveyor to the receiving end of the platform,

conveyor to the receiving end of the platform,

arms carried by the clamps each of sufiicient length to push the foremost can through said passageway and onto the platform, and means for arresting the travel of the nextto the foremost can until the foremost can has been shunted off the belt conveyor and into said lateral passageway. r

10. A specific embodiment of. the combination defined .in claim 3, wherein the means for successively feeding the cans onto one end of the platform comprises abelt conveyor, a can stop at the delivery end of said conveyor, a lateral passageway leading from the delivery end of said conveyor to the receiving end of the platform, arms carried by the clamps each of sufiicient length to push the foremost can through said passageway and onto the platform, a pivoted finger for arresting the travel of the next to the foremost can until the foremost can has been shunted off the belt conveyor and into said lateral passageway, a latch normally locking said finger in operative position, a spring-actuated cam-controlled lever for releasing said latch as soon as the foremost can has passed into said lateral passageway, and springs for returning said finger and latch to normal interlocked position. 1

by the flange, said heating and squeezing action being continued until the outer surface of the flange is flush with the outer surface of the body.

12. The herein described method of transforming an over-size cap can into a flush type can after the can has'been filled with product, which consists in squeezing the flanges of the caps on the ends of the body at right angles cap to a pasteboard can body, which consists in 11. A method of applying a flanged pasteboard I pasteboard sheet, telescoping the cap flange over an open end of the can body, and then heating ,and squeezing the dampened flange at right an-' gles to the axis of the cap, to compress and inwardly offset the portion of the body covered y ing action being continued until the outer surmoistening the cap flange, then telescoping the caponto an open end of the body, and then gradually applying external squeezing pressure to the moist flange at right angles to the axis 'of the cap suflicient to compress and inwardly oifset the portion of the body covered by the flange, said pressure applying action being continued until the outer surface of the flange is flush with the outer surface of the body,

14. A method of applying a flanged pasteboard cap to a pasteboard can body, which consists in moistening the cap flange, then telescoping the cap onto an open end of the body, and then heating and gradually applying external squeezing pressure to the moist flange at right angles to the axis of the cap sufliciently to compress and inwardly offset the portion of the body covered by the flange, said heating and pressure applying action being continued until the outer surface of 'the flange is flush with the outer surface of the body.

15. A method of applying a moist, flanged pasteboard cap to a pasteboard can body, which consists in telescoping the caponto an open end of the body, and then gradually applying external squeezing pressure to the moist flange at right angles to the axis of the cap suflicient to compress and inwardly offset the portion of the body covered by the flange, said pressure applyface of the flange is flush with the outer surface r the body; I 1

; LESTER L. LADD. 

